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What's That Bug? does not endorse extermination

Creosote Gall

Gall or nest?
August 3, 2009
Hi guys!
I absolutely love your site, and tell all my friends about it! I found a very alien object clinging to a creosote bush behind my house, in Tucson AZ. It is a leafy sphere, about the size of a quarter. The leaves (which don’t look anything like those the creosote leaves) are arranged in whirls, like a grassy daisy, and there is a tiny hole in the center of each. Coming out of each hole are discarded exoskeletons, like those of the grain moth larvae you find in boxes of rice and pancake mix. They are probably only 4 or 5mm long. There is also a bit of silk strewn around the whole thing, which gives it a dewy, sticky look, but I haven’t touched it because I don’t want to be impregnated by some alien insectoid race. What kind of bug could construct such a crazy looking (and beautiful) nest? Or is it a gall of some sort? I am so very curious…
Thanks for your help!
Emily Rush
Tucson, Arizona, USA

Creosote Gall

Creosote Gall

Creosote gall
August 3, 2009
Hi!
Me again. After writing to you, I decided to google “creosote gall”. Don’t know why I didn’t do that first, I guess I was just excited to send you a pic of something you might not have seen before. Apparently my mystery alien sphere IS a gall, caused by, wonder of wonders, a creosote gall midge! I couldn’t find a picture of one though. Any help in this area?
Thanks again!
Emily Rush
Tucson, Arizona, USA

Hi Emily,
Thanks for sending us your photo of a Creosote Gall and doing the subsequent research.  BugGuide has images of the Creosote Gall filed under the species Asphondylia auripila with the information:  “Larvae form galls in creosote bush (Larrea tridentata),” but if you go to the genus Asphondylia and browse, you will see some images of related Midges that probably look very similar to the Creosote Gall Midge. The only species on BugGuide with images of adults is Asphondylia solidanginis. Species in the same genus often have visual similarities and an expert is required to differentiate one from another.  Unlike the Oak Gall we just posted which was formed by a small wasp, the Creosote Gall is formed by a Midge that is in the order Diptera and is classified with the flies.  The Creosote Gall is a deformation of the plant with the leaves and stems stunted to form the Gall.  If you follow the taxonomy on BugGuide back to the Family Cecidomyiidae, you start to get a bit more information, including:  “Minute, delicate flies with long legs and usually relatively long antennae, and with reduced wing venation” and “more than 1,200 species in 170 genera in North America.” There are images of many different species on the Cicidomyiidae page of the Forestry Images website.  Some of the members of the family include the Skeletonweed Gall Midge and the St. John’s Wart Midge.  Those should give you some idea of what the Creosote Gall Midge looks like.  Again, thanks for sending us your photo.

Thanks Daniel!
I hope I can catch a midge in action. By the way, the root borer you posted is a Palo Verde beetle (Derobrachus geminatus). We have lot’s of them in Tucson- they’re HUGE, and they’re really active right now, during the monsoon. I like their fancy spiked collars! Here’s another!
Emily

Posted 03 August 2009 § Midges ‡ Comments (2) °

Oak Apple or Oak Gall

Insect egg ball
July 31, 2009
Hi,
I keep finding these egg balls under an oak tree in my yard. Can you tell me what comes out of these? (The second picture shows their exits.) The wall material is paper thin and very brittle. They are about the size of a golf ball, beige, and bumpy.
Thank you.
Todd Shinn
Salisbury, NC

Oak Gall

Oak Gall

Hi Todd,
This is the Gall or Oak Apple formed by some species of Gall Wasp, a tiny wasp in the family Cynipidae.  The larval Gall Wasp creates the Gall as part of its growth process and the Galls do not harm the trees. There are numerous species and according to BugGuide: “Many different cynipid wasps form large, spherical galls on oak leaves, some of which are called “oak apples.” As with most galls, ID requires knowing the species of oak. It is also critical to look at the internal structure:  Even then, there are some very similar ones, and it may be necessary to examine the adult wasp that emerges.“  A British Website has a photo that matches your Gall, and it is identified as Biorhiza pallida, but we believe your new world species is not the same. According to BugGuide there are  “Over 750 species in North America in 49 genera” and “Small to minute, usually black, with characteristic shape: the abdomen is oval and somewhat compressed and shiny, the second tergum covers a good part of the abdomen. Each species makes a characteristic gall on a specific part of the plant. Many make galls on oaks. Most have a complex life cycle with a parthenogenetic generation and a sexual one. Each generation makes galls of a different appearance and on different parts of the plant.“ The recognized expert in this family is Charles Kinsey who died about 50 years ago after achieving worldwide fame for his studies of male and female sexuality.

Posted 02 August 2009 § ‡ Comments (0) °

Oak Galls

I found cocoon-like brown hard masses on the front side of a leaf.What are they???
Wed, Oct 8, 2008 at 6:13 PM
I was sweeping off the porch at the campground that I stayed at during the summer/fall.We had a big wind storm come thru and there were a bunch of leaves on the porch.On a lot of the leaves,I noticed these little hard brown cocoon-like circles on the front side of a leaf.I was thinking that cocoons were laid on the under part of the leaf,and that they were soft to touch,but these are hard and round.So I decided to cut one open and inside are these tiny red-orange color worm-like things inside.They moved a little bit,so I just thought that they were a worm of some kind.I’ve looked all over the internet and came up with nothing.Finally I posted my question and someone told me to contact you.I have pictures of the “cocoons” and the “worms” inside.The worms are very small and hard to see on the picture.Please help me identify w hat I’ve found!
Curious Nature Lover
Shreve,Ohio

Oak Leaf Galls

Oak Leaf Galls

Dear Curious,
Galls are growths on plants that may be caused by insects, mites, bacteria or fungus.  The Galls may occur on the leaves, stems, roots or flowers of the plants.  Most often, the Galls are plant specific.  We located a drawing in a very old copy of a text by Frank E. Lutz that we own.  The drawing is of a Oak Leaf Gall known as Dryophanta polita.  Since the text is a field guide, there was no additional information beyond the identification.  When we tried a web search of that name, be were led to several online texts that we could not access entirely.  One such text is Insects Affecting Park and Woodland Trees and the google teaser is “Oak leaf bullet gall Dryophanta polita Bass. A small, globular gall occurs in
numbers in August … “  Another reference led to the common name Polished Oak Gall.  At this point, we can only speculate that Dryophanta polita is a Gall Wasp in the family Cynipidae, but curiously, it is not listed in BugGuide’s taxonomy for the family.  Another interesting side note is that Alfred Kinsey, most widely known for his studies of human sexuality and his best selling books in the 1950s, was first and foremost an entomologist who specialized in Gall Wasps.

Dissected Oak Leaf Galls

Dissected Oak Leaf Galls

Posted 09 October 2008 § ‡ Comments (0) °
What's That Bug? does not endorse extermination

Oak Leaf Gall: Amphibolips coelebs

???eggs on bur oak leaf?????
HI,
I just took a photo of these bug eggs???? on the leaves of our bur oak tree today (Sept 22, 2008) . The eggs are hard (so my husband say’s I couldn’t get up the nerve to touch them). So it’s the beginning of fall here in Iowa. I was wondering if you could identify the egg for us. Our son who’s 4 spotted them on the tree. There are only a few leaves with the clusters. After trying to identify these in a few books and the help of your web site our 4 year old said why don’t you ask that cool web site we go to….so here I am asking for help.
Thanks so much for your time.
The Sims Family
Des Moines, Iowa

Oak Leaf Gall

Oak Leaf Gall

Dear Sims Family,
Though they might look like eggs, they are actually Galls.  Galls are growths on plants caused by insects, mites or other creatures.  We believe your Galls are Amphibolips coelebs and they are caused by a tiny Gall Wasp.  We identified them thanks to a wonderful old research book written by Frank E. Lutz, but we couldn’t find an image online.  Galls don’t generally cause the plants any harm.  In the case of the Gall Wasps, the growth creates a food source for the developing larva.

Posted 22 September 2008 § ‡ Comments (0) °

Unknown Gall from Panama

tropical gall
Hi,
Your gall page is great! Any idea what insect might be producing this gall? I’m pretty sure the tree is in the Myrtaceae family, but beyond that, I couldn’t say. The tree is in western Panama at an altitude of about 800 m. Thanks for any help.
Mary

Hi Mary,
We don’t know anything about your Gall from Panama. It is unusual in that it is a twig gall and not a leaf gall. We will post your photo to see if any of our readers knows the answer, but you shouldn’t get your hopes up too high for an identification. Tropical insects are even difficult to identify when they are large, spectacular looking, or highly unusual, unlike this relatively innocuous Gall.

Posted 28 June 2008 § ‡ Comments (0) °

Grape Tube Gallmaker

Eggs on Scuppernong
Hi, I stumbled upon your great website while trying to find out what these apparent eggs are on a Scuppernong (wild) leaf in our front yard woods here in Northeastern Alabama. Got any ideas? Many thanks for any help.
Mike O’Brien

Hi Mike,
Your letter attracted our attention since we had no idea what a Scuppernong was. Thanks to Wikipedia, now we know a Scuppernong is a Wild Grape. These are Grape Tube Gallmakers formed by a Midge, Cecidomyia viticola. Dave’s Garden website has photos. Galls are growths on plants caused by insects (like wasps, flies or aphids), mites, fungus, bacteria, viruses and other sources. Galls can be found on leaves, stems, roots, buds and other plant parts. Most Galls are harmless, though unsightly, and a few are destructive. The Grape Tube Gallmaker is an example of a harmless Gall. The larval Midge forms the Gall and the Gall acts as the food source for the insect. The are

Posted 20 June 2008 § ‡ Comments (0) °

Wool Sower Gall

Cocoon on Oak Tree Branch?
Hi — I found your website through Google. I live in central Missouri and found this "weird growth" on a branch of one of the oak trees in my yard. I’ve tried researching the web, but I still can’t identify if it’s a plant fungus, or a gall, or a bird nest, or a cocoon, or something else! Do you have any idea? It’s about the size of a ping-pong ball, white with pink spots, and it’s "perched" on top of the branch. Very strange. Thanks!
Susan Foster

Hi Susan,
In the true sense of the word, this is not a cocoon though adult insects will emerge. You have a Wool Sower Gall which is produced by a tiny wasp, Callirhytis seminator. Galls are growths on various parts of plants, usually caused by a Gall Wasp or a type of mite. There are many species of Gall Wasps, and each has a specific host plant. The Wool Sower Gall used the oak tree as a host. Here is a site with additional information.

Posted 10 May 2008 § ‡ Comments (0) °

Gall on California Black Walnut Tree: Velvet Gall Mite???

Yesterday we noticed this gall on our largest protected California Black Walnut Tree, and did some internet research. We can’t locate a convincing photo, but believe it might be the result of the Velvet Gall Mite, Eriophyes caulis. We will check with local California Black Walnut experts Clare Marter-Kenyon and Julian Donahue to see if they know of this mite on Los Angeles trees. According to the information we can locate: “Little is known about the mites that occur on black walnut, but the velvet gall mite is common in some areas. The mite itself is so small that it cannot be seen with the unaided eye. Injury The velvet gall mite causes a conspicuous velvety red growth up to an inch long on the leaf stem, often causing the leaf to curl or twist over on itself. Galls may be numerous on individual trees but they are considered to be harmless to the tree. Control No control is recommended. ”

Posted 02 May 2008 § ‡ Comments (0) °

Oak Apple Galls

unusual oak galls?
Hi,
First, I love your site! These odd-looking galls appeared on some oak trees in my yard last year and they’re back this year. I can’t seem to identify them anywhere on the internet. I suspect they are wasps of some kind and don’t want to eliminate them if they’re harmless. My dog, a golden retriever, actually ate a few them today! GROSS! I assume since the squirrels eat them they must not be toxic. (?) Thanks in advance for any help in identifying what kind of creature is in there…
a bug lover

Hi Bug Lover,
We believe these are Oak Apple Galls, benign leaf galls produced by the Gall Wasp, Amphibolips confluenta, a “very small and dark cynipid wasps with an oval, compressed abdomen” according to a website we located. Another website indicates that several wasps produce Oak Apple Galls, also known as King Charles’ Apple. One species mentioned is Biorhiza pallida.

Posted 15 March 2008 § ‡ Comments (0) °

Spiny Rose Galls

Rose Galls
Just thought I’d share this pic of Rose galls – presumably from a gall wasp. Enjoy!
Barbara Logan
Fairbanks, Alaska

Hi Barbara,
After a bit of research, we believe these Galls to be either the Spiny Rose Gall, Diplolepis bicolor, or another related rose leaf gall, Diplolepis polita, and not the picturesque Robin’s Pincushion, Diplolepis rosae.

Posted 04 February 2008 § ‡ Comments (0) °

Two Species of Leaf Gall

Hi – I wondered if you could identify the above images? The first one was on an elm tree – the whole tree was coveredin them. The second one (Oak ‘eggs’) was on the leaf until it dropped off in the autumn – what happened then I don’t know. They started out bright red but by autumn were a very pale pink. Many thanks!
Jo

Hi Jo,
Both of your photos illustrate Galls, growths that occur on various parts of plants that are usually caused by an insect or mite. Wasps, Moths, Aphids and Flies can all produce Galls. According to the University of Kentucky College of Agriculture website: “Galls are irregular plant growths which are stimulated by the reaction between plant hormones and powerful growth regulating chemicals produced by some insects or mites. Galls may occur on leaves, bark, flowers, buds, acorns, or roots. Leaf and twig galls are most noticeable. The inhabitant gains its nutrients from the inner gall tissue. Galls also provide some protection from natural enemies and insecticide sprays. Important details of the life cycles of many gall-makers are not known so specific recommendations to time control measures most effectively are not available.” Galls are not harmful to the plant. Regarding your images, we are not entirely conviced that the tree you indicate is an elm is really an elm. Also of interest with the color change in the Oak Galls is this citation from Lutz’ Field Book of Insects: “Of the Galls caused by insects, Oak Galls have been used in dyeing, tanning, and the manufacture of ink.”

Hi Daniel – thank you very much for your reply. I thought they may be galls but wasn’t sure. The tree was identified by a wildlife trust (I work for them so quite a few people saw the leaves and said they were elm). However no one was sure what the ‘lumps’ were. Have a good Christmas Best wishes
Jo

Posted 20 December 2007 § ‡ Comments (0) °

Crystaline Gall Wasp

Lovely red stranger on oak leaves
Can you identify these red beauties attached to the base of some of the oak leaves in our backyard in Pleasant Hill, California? I included a picture of the oak leaves to assist you in identifying the type of oak – I’m not sure what type it is. Thank you!
Mabel Neys
Pleasant Hill, California

Hi Mabel,
We have been scouring the web for about an hour trying to properly identify your Oak Gall, probably to the chagrin of our other readers with questions sitting in our “in box”. Sadly, we will have to leave this identification at Unknown Oak Gall, probably one of the Gall Wasps in the family Cynipidae, and possibly in the genus Andricus based on the closest image we could find on BugGuide, Andricus fullawayi. We decided to give it one more try and located Andricus crystallinus, the Crystalline Gall Wasp. Looks like a perfect match. Galls do not harm the oak trees.

Posted 10 August 2007 § ‡ Comments (0) °

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